Britain's competition watchdog said Wednesday that Facebook and eBay pledged to crack down on the trade in fake reviews at its request, removing hundreds of accounts, pages and groups involved in the illicit business.

The Competition and Markets Authority said the two US tech companies agreed to step up efforts to detect, investigate and respond to fake and misleading reviews after it ordered them last year to address the problem.

Facebook removed 188 pages and groups and disabled 24 accounts that were involved in the fake review trade, some on its Instagram platform. Some of the pages and groups were identified by the agency, others were found by Facebook.

Some of the groups offered in online posts to write fake reviews for payment or in exchange for products. Others recruited people to write them on shopping and review sites.

The regulator also said eBay permanently banned 53 users who were selling fake review services on the auction site and temporarily suspended another 176 users.

Facebook agreed to beef up its systems to detect and remove fake review material while eBay refined its existing filters to better identify and block listings for online review services, the CMA said.

Fake reviews are really damaging to shoppers and businesses alike, the regulator's chief executive, Andrea Coscelli, said in a statement.

Millions of people base their shopping decisions on reviews, and if these are misleading or untrue, then shoppers could end up being misled into buying something that isnt right for them - leaving businesses who play by the rules missing out.

EBay said it has zero tolerance for fake or misleading reviews and will continue to take action against any seller that breaches our user polices.”

Facebook said it has invested heavily to stop people offering or trading fake review services on its platforms, but we know there is more work to do and are working with the CMA to address this issue.